Instead of sulking, though, United are trying to get on with the rest of their season as vigorously as they can. They brushed aside Birmingham City at St Andrew’s last night to reach the semi-finals of the Carling Cup and although it hardly bears comparison to the Champions League, it at least keeps alive the prospect of winning silverware. Without a trophy in nearly two years, United cannot be choosy.

It is United’s tenth last-four appearance in the competition. They lost to Chelsea in the two-leg semi-final last season and, strangely, have won it only once. Yet Sir Alex Ferguson, their manager, concedes that it has suddenly taken on extra importance.

United have to win something this season, anything. If they could enter the LDV Vans Trophy, they probably would. “If the opportunity is there in any cup, you have to go for it,” Ferguson said. “I felt that we were unlucky against Chelsea last season.”

For Steve Bruce, the Birmingham manager, the misery goes on. Although his much-changed side, a reaction to the “pathetic” 4-1 defeat against the other side in Manchester on Saturday, competed well in the first half, they were blown away after the interval. Wayne Rooney, a substitute, did not contribute directly to the three United goals but being there was enough. “I think his presence helped a bit,” Ferguson said.

Despite a flurry of league defeats, Bruce’s job appears to be safe, if you believe the vote of confidence given to him by David Gold, the Birmingham chairman, on Monday. Only 20,454 fans turned up last night, the club’s lowest crowd of the season, but Bruce was encouraged by what he saw in the opening 45 minutes. “I was very pleased with the opening half,” he said, “which was probably proved by United having to bring on a certain big name at half-time. We got a bit of our pride back and we stuck at it.”

However, with troubled times at St Andrew’s and the fans perhaps not sharing Gold’s confidence in Bruce, the former United defender was unwise to acknowledge the United fans when they chanted his name in the second half. Some of the home supporters booed Bruce for his response. “I’ve been here four years as a manager and two as a player and the fans know exactly what I think of this club,” he said.

Birmingham were initially nervous and disorientated as United swarmed all over them. Guiseppe Rossi half-volleyed against the crossbar from John O’Shea’s cross and Cristiano Ronaldo thundered in a long-range free kick that Maik Taylor did well to gather. Louis Saha headed wide of an open goal, but Tim Howard made an excellent save from Emile Heskey as the first half drew to a close.

However, within five minutes of the second half, United had effectively ended the contest. Louis Saha bundled in the opener from close range from Ronaldo’s low cross, just 37 seconds into the period, and then Park Ji Sung walloped home a fierce shot for his first goal since joining United from PSV Eindhoven during the summer.

A seventh home defeat in all competitions this season beckoned for Birmingham, whose promise had long evaporated, and it was confirmed in the 63rd minute when Gary Neville supplied the pass for Saha to make it 3-0 with an emphatic finish. Jiri Jarosik plundered a late consolation goal, glancing in Jermaine Pennant’s free kick, but it counted for little.

The gloom may be lifting at Old Trafford but it is starting to envelop St Andrew’s. Bruce has a tough task.

BIRMINGHAM CITY (4-4-2): Maik Taylor — D Johnson, Martin Taylor, M Upson, M Painter — J Pennant, N Butt (sub: J Clapham, 66min), S Clemence, D Dunn (sub: N Kilkenny, 66) — J Jarosik, E Heskey (sub: M Forssell, 83). Substitutes not used: C Doyle, W Pandiani. Booked: Johnson.

MANCHESTER UNITED (4-4-2): T Howard — G Neville, W Brown, M Silvestre (sub: R Ferdinand, 60), K Richardson — C Ronaldo, D Fletcher, J O’Shea (sub: R Jones, 66), Park Ji Sung — G Rossi (sub: W Rooney, 46), L Saha. Substitutes not used: E van der Sar, P Bardsley. Booked: Silvestre, Richardson.

Referee: M Halsey.